[TLI] Add prototype checking for all remaining LibFuncs.

[TLI] Add prototype checking for all remaining LibFuncs.

This is another step towards unifying all LibFunc prototype checks.
This work started in r267758 (D19469);  add the remaining checks.

Also add a unittest that checks each libfunc declared with a known-valid
and known-invalid prototype.  New libfuncs added in the future are
required to have prototype checking in place; the known-valid test will
fail otherwise.

Differential Revision: https://reviews.llvm.org/D28030

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292188 91177308-0d34-0410-b5e6-96231b3b80d8